1. Field of the Invention
This invention relates to an electronic clinical thermometer and, more particuarly, to an electronic clinical thermometer which includes means for sensing the temperature of a portion of the human body, arithmetic means for predicting, based on the sensed body temperature, the final temperature at which the thermometer will stabilize, and means for displaying temperature. The invention further relates to a method of measuring body temperature.
2. Description of the Prior Art
In the prior art arrangement, the temperature which will prevail upon thermal stabilization of the electronic clinical thermometer is predicted from measured temperature and is displayed before thermal stabilization is attained. Typically, prediction of temperature is performed by monitoring, over a period of time, the measured temperature as well as the rate of change thereof with time, and employing these two variables along with a function for predicting temperature in which the variable is the elapsed time up to the moment of observation. The predicted final, stable temperature is uniquely defined by the actual values of these three variables.
With an electronic clinical thermometer that operates by predicting the final, stable temperature, measurement of temperature is completed before thermal stabilization is attained, thereby reducing the time required for measurement. However, a disadvantage with such a thermometer is that the accuracy with which temperature is predicted declines markedly unless a proper temperature prediction function is chosen.
Ordinarily, the temperature prediction function has a temperature rise curve the shape whereof differs depending upon the portion of the body being measured, such as the region under the armpit or the interior of the mouth. The conventional electronic clinical thermometer possesses only a single temperature prediction function for measuring body temperature orally or by placement in the armpit. An electronic clinical thermometer having both of these functions for measurement of both regions is not available. Another disadvantage with the conventional electronic clinical thermometer is that the predicted value of the final, stable temperature is displayed, and the value retained, after the elapse of a predetermined period of time or when a prescribed rate of change of temperature has been observed. The accuracy of the temperature prediction is decided by this display and retention of the predicted value. Accordingly, there is insufficient freedom to effect any improvement in temperature prediction which might be required. It is desired, therefore, that a final temperature, reached upon stabilization, be computed with greater accuracy by continuing measurement, even after a final temperature has been predicted and displayed, rather than suspending measurement and anticipatory computations at such time.